GB395714A - Improvements relating to armature windings for dynamo electric machines - Google Patents

Abstract

395,714. Coils and windings for dynamo-electric machines. PRITT, S. E., 36, Abbeydale Park Rise, Totley Rise, Sheffield, and ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Crown House, Aldwych, London. Jan. 19, 1932, No. 1660. [Class 35.] A two-turn coil for the armature of a dynamoelectric machine having stepped or tapered slots is obtained by cutting from a bar or strip 1, tapered or stepped in cross-section, two U- shaped blanks 2, 3 as shown in Fig. 1 ; one of the blanks is turned end for end, and the free ends of the inner bars 4, 5 are joined together by a cleft 8 forming a coil as shown in Fig. 3. The bars 6, 4 occupy the outermost and the next to the outermost positions in a slot and the bars 7, 5 the innermost and the next to the innermost positions in another slot. The free ends of the conductors 6, 7 are secured to commutator risers and may be pressed or shaped to a suitable size. The cuts in the conductor strip may be formed by punching, shearing or stamping, and the cross-sections of the resulting straight portions are preferably equal. A number of coils may be located side-by-side in the slots, all the coils occupying the upper half of one slot and the lower half of another being insulated by a common sheath before insertion in the slots. In order to improve commutation, the two turns comprising a coil may occupy different positions in the circumferential direction as shown in Fig. 7. Specification 349,975 is referred to.